Regex Tester
Test, debug, and match your Regular Expressions against text in real-time.
About Regex Tester
Writing complex regular expressions? The Free Regex Tester helps you validate patterns instantly. As the Best Regex Tester, it allows you to test regular expression logic against live text and find all matching groups securely.
Features
- Real-time regex matching and syntax highlighting
- Supports global (g), case-insensitive (i), and multiline (m) flags
- Displays capture groups and match indices
- Infinite loop protection built-in
- Client-side Javascript regex engine
How to Use
- Enter your Regular Expression pattern at the top.
- Toggle any necessary flags (g, i, m).
- Type or paste your test text in the main body.
- Review the highlighted matches and capture groups below.
Frequently Asked Questions
Which regex engine does this use?
It uses the native JavaScript (ECMAScript) Regular Expression engine running in your browser.
What does the "g" flag do?
The "g" (global) flag tells the engine to find all matches in the text, rather than stopping after the first match.
Are capture groups supported?
Yes, if you use parentheses in your regex, the tool will extract and display those specific capture groups.
Is it safe to test sensitive logs?
Yes, since the processing is strictly local, you can safely test private log files or database dumps.
Which Regex flavor does this use?
It uses standard JavaScript (ECMAScript) regular expressions.
Can I test global and multiline flags?
Yes, you can toggle flags like global (g), case-insensitive (i), and multiline (m).
Does it highlight matches in real-time?
Absolutely. As you type your regex or test string, matches are highlighted instantly.
Is this a free regex tester?
Yes, use this free regex tester to debug your patterns at no cost.
Does the best regex tester support different flags?
Yes, you can test regular expression strings with global, multiline, and case-insensitive flags.
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